Rafael A. Irizarry
polls_2008 %>% select(start_date, Obama, McCain)
Source: local data frame [543 x 3]
start_date Obama McCain
(time) (dbl) (dbl)
1 2008-11-03 0.52 0.43
2 2008-11-02 0.49 0.44
3 2008-11-01 0.51 0.46
4 2008-11-01 0.52 0.44
5 2008-11-01 0.52 0.46
6 2008-11-01 0.53 0.45
7 2008-10-31 0.54 0.43
8 2008-10-30 0.52 0.44
9 2008-11-02 0.53 0.44
10 2008-11-01 0.51 0.43
.. ... ... ...
\( f(x) = \mbox{E}(Y \mid X=x) \) is not a line.